Ferrite Core Transformer Power Loss

hi,

What is the acceptable level/range of Core power loss in a 500W Full-bridge Converter working at 100Khz? And how can i calculate temperature rise in the core?

Regards

The acceptable level depends on the intended efficiency. I won't accept more than 1, maximal 2 percent transformer (core + copper) losses.

Core manufacturers (e.g. Epcos/TDK, Ferroxcube) have calculation tools for transformer design.

yes look up Epcos ferrite core databook, or ferroxcube ferrite core databook..............you will see graphs which show Watts/Kg for various switching frequencies and peak currents.

Be careful though as sometimes the current refers to peak to peak value, and sometimes to peak value.

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To be honest the acceptable power loss depends on the method of cooling you are using…if you have good cooling you can run so much hotter. Get the” Magnetic Design Tool” software from EPCOS (or TDK?). this gives some advice.
To be honest, to overheat a ferrite core takes some serious power dissipation in it…to make a ferrite core go over the curie temperature you really need to get up above 180degC.

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You can always have a small gap between the top of the ferrite core and the metal enclosure casing, and then have a bit of gap pad between the two so that the ferrite core heat is somewhat coupled to the metal enclosure casing…if this is acceptabel to your design.